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1.
Chem Commun (Camb) ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38993023

RESUMO

Metal-free, photoredox-catalyzed aromatization-driven deconstructive functionalization of spiro-dihydroquinazolinones with α-CF3 alkenes is presented. The readily available spiro-dihydroquinazolinones reacted efficiently with α-CF3 alkenes during photocatalysis to give the gem-difluoroallylated and the CF3-containing quinazolin-4(3H)-ones in good yields with excellent chemoselectivity. The selectivity depends on the electron effect of substituents in α-CF3 alkenes. A wide range of four-, five-, six-, seven-, eight- and twelve-membered spiro-dihydroquinazolinones were compatible with this transformation. The protocol is also characterized by the mild and redox-neutral reaction conditions, good functional group compatibility and excellent atom economy. Mechanistic studies revealed that the reaction proceeds via a radical pathway.

2.
Org Lett ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976347

RESUMO

A photoredox-catalyzed sequential decarboxylative/defluorinative aminoalkylation of CF3-alkenes with N-arylglycines is described. This metal-free and redox-neutral protocol provided efficient access to the monofluoroalkenyl-1,5-diamines in good yields with excellent functional group compatibility. Mechanistic studies revealed that the reaction proceeds via a radical pathway with the gem-difluoroalkenyl amine as an intermediate.

3.
Asian J Androl ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38856299

RESUMO

ABSTRACT: Male infertility is a global issue caused by poor sperm quality, particularly motility. Enhancement of the sperm quality may improve the fertilization rate in assisted reproductive technology (ART) treatment. Scriptaid, with a novel human sperm motility-stimulating activity, has been investigated as a prospective agent for improving sperm quality and fertilization rate in ART. We evaluated the effects of Scriptaid on asthenozoospermic (AZS) semen, including its impact on motility stimulation and protective effects on cryopreservation and duration of motility, by computer-aided sperm analysis (CASA). Sperm quality improvement by Scriptaid was characterized by increased hyaluronan-binding activity, tyrosine phosphorylation, adenosine triphosphate (ATP) concentration, mitochondrial membrane potential, and an ameliorated AZS fertilization rate in clinical intracytoplasmic sperm injection (ICSI) experiments. Furthermore, our identification of active Scriptaid analogs and different metabolites induced by Scriptaid in spermatozoa lays a solid foundation for the future biomechanical exploration of sperm function. In summary, Scriptaid is a potential candidate for the treatment of male infertility in vitro as it improves sperm quality, prolongs sperm viability, and increases the fertilization rate.

4.
Org Lett ; 26(26): 5482-5487, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38913035

RESUMO

An efficient synthesis of quinoxaline-fused aza-bicyclo[2.1.1]hexanes bearing multiple quaternary carbon centers via the intermolecular [2π+2σ] cycloaddition of bicyclo[1.1.0]butanes and quinoxalin-2(1H)-ones, facilitated by Lewis acid catalysis, is presented. This reaction is carried out under mild conditions and exhibits a broad substrate scope and excellent functional group tolerance.

5.
Chem Sci ; 15(23): 8993-8999, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38873081

RESUMO

Aromatization-driven deconstruction and functionalization of spiro dihydroquinazolinones via dual photoredox/nickel catalysis is developed. The aromatization effect was introduced to synergistically drive unstrained cyclic C-C bond cleavage, with the aim of overcoming the ring-size limitation of nitrogen-centered radical induced deconstruction of carbocycles. Herein, we demonstrate the synergistic photoredox/nickel catalyzed deconstructive cross-coupling of spiro dihydroquinazolinones with organic halides. Remarkably, structurally diverse organic halides including aryl, alkenyl, alkynyl, and alkyl bromides were compatible for the coupling. In addition, this protocol is also characterized by its mild and redox-neutral conditions, excellent functional group compatibility, high atom economy, and easy scalability. A telescoped procedure involving condensation and ring-opening/coupling was found to be accessible. This work provides a complementary strategy to the existing radical-mediated C-C bond cleavage of unstrained carbocycles.

6.
Mycopathologia ; 189(3): 35, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637433

RESUMO

Candida auris, an emerging and multidrug-resistant fungal pathogen, has led to numerous outbreaks in China. While the resistance mechanisms against azole and amphotericin B have been studied, the development of drug resistance in this pathogen remains poorly understood, particularly in in vivo-generated drug-resistant strains. This study employed pathogen whole-genome sequencing to investigate the epidemiology and drug-resistance mutations of C. auris using 16 strains isolated from two patients. Identification was conducted through Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antimicrobial susceptibilities were assessed using broth microdilution and Sensititre YeastOne YO10. Whole-genome sequencing revealed that all isolates belonged to the South Asian lineage, displaying genetic heterogeneity. Despite low genetic variability among patient isolates, notable mutations were identified, including Y132F in ERG11 and A585S in TAC1b, likely linked to increased fluconazole resistance. Strains from patient B also carried F214L in TAC1b, resulting in a consistent voriconazole minimum inhibitory concentration of 4 µg/mL across all isolates. Furthermore, a novel frameshift mutation in the SNG1 gene was observed in amphotericin B-resistant isolates compared to susceptible ones. Our findings suggest the potential transmission of C. auris and emphasize the need to explore variations related to antifungal resistance. This involves analyzing genomic mutations and karyotypes, especially in vivo, to compare sensitive and resistant strains. Further monitoring and validation efforts are crucial for a comprehensive understanding of the mechanisms of drug resistance in C. auris.


Assuntos
Antifúngicos , Candidíase , Humanos , Antifúngicos/farmacologia , Candidíase/microbiologia , Candida auris , Candida , Anfotericina B/farmacologia , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana
7.
Chem Commun (Camb) ; 60(40): 5334-5337, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38668748

RESUMO

A photoredox-catalyzed alkylarylation of activated alkenes via a radical C-C bond cleavage/Truce-Smiles rearrangement cascade is developed. The protocol features mild and redox-neutral conditions, broad substrate scope and excellent functional group compatibility, providing a facile and efficient approach to the long-chain distal keto-amides with all-carbon quaternary centers at the alpha position.

8.
NPJ Parkinsons Dis ; 10(1): 70, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548756

RESUMO

This study aimed to investigate the association between irritable bowel syndrome (IBS) and Parkinson's disease (PD) utilizing prospective cohort study and Mendelian randomization. The dataset contained a substantial cohort of 426,911 participants from the UK Biobank, discussing the association between IBS and PD with Cox proportional hazards models and case-control analysis while adjusting for covariates such as age, gender, ethnicity and education level. In univariate Cox regression model, the risk of PD was reduced in IBS patients (HR: 0.774, 95%CI: 0.625-0.956, P = 0.017), but the statistical significance diminished in the three models after adjusting for other variables. In a few subgroup analyses, IBS patients are less likely to develop into PD, and patients diagnosed with IBS after 2000 also had a lower risk (HR: 0.633, 95%CI: 0.403-0.994, P = 0.047) of subsequently developing PD. In addition, we matched five healthy control participants based on gender and age at the end of the study for each IBS patient diagnosed during the follow-up period, and logistic regression results (OR:1.239, 95%CI: 0.896-1.680, P = 0.181) showed that IBS was not associated with the risk of PD. Mendelian randomization did not find significant evidence of the causal relationship between IBS and Parkinson's disease (OR: 0.801, 95%CI: 0.570-1.278, P = 0.204). Overall, we suggest that IBS status is not associated with the risk of developing PD, and that these findings provide valuable insights into the clinical management and resource allocation of patients with IBS.

9.
Org Lett ; 26(11): 2266-2270, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38451860

RESUMO

A sustainable, cyanide-free synthesis of alkyl nitriles via the aerobic oxidative deconstruction of unstrained cycloalkanones with ammonium salts has been developed. Using inexpensive and stable ammonium salts as the nitrogen source, a variety of alkyl nitriles containing a distal carbonyl group were obtained in good yields under visible-light-promoted iron catalysis. This protocol is characterized by mild conditions, abundant and environmentally benign materials, and high atom and step economy with minimal waste generation. The primary mechanism study revealed that 1O2 is likely to be involved in this reaction.

10.
Nat Prod Res ; : 1-5, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37888852

RESUMO

Two new furanone derivatives, byssochlanones A-B (1-2) were purified from the endophytic fungus Byssochlamys sp. isolated from the wetland plant, Phragmites australis. Their structures were elucidated on the basis of extensive spectroscopic analyses. Compounds 1-2 represented typical furanone analogues which are not common in natural products. The absolute configuration of compounds 1-2 were identified through quantum-chemical electronic circular dichroism (ECD) calculation compared with their experimental CD. In addition, compounds 1-2 were tested for their cytotoxic activities against HCT-8 and Hela cancer cell lines, and compound 2 showed moderate activity against HCT-8 cells with IC50 value of 21.3 µM.

11.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2405-2412, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37899106

RESUMO

The development and utilization of coastal saline-alkali lands hold significant importance in mitigating the shortage of cultivated land resources in China, enhancing the agro-ecological environment in coastal saline and alkaline areas, and ensuring national food security. We set up both pot and field trials (randomized block design) at Xinxiang experimental station of Institute of Crop Science, Chinese Academy of Agricultural Sciences (ICS-CAAS) and Dongying Yellow River Delta Modern Agricultural Research Base in Shandong Province in 2021 and 2022, respectively. The experimental materials, Jiliang 1 and Jiliang 2, underwent seed dressing with GKI composites at concentrations of 2.5 and 5 mL·kg-1. These composites, which contained the main components of gibberellin, kinetin, and indole butyric acid, were denoted as GKI2.5 and GKI5.0, respectively. The control plots (CK) received water seed dressing. The aim was to assess the regulatory effects of GKI on salt tolerance and grain sorghum yield. Compared to CK, the GKI2.5 and GKI5.0 seed dressing treatments significantly enhanced the growth and development of the two grain sorghum varieties, increased antioxidant enzyme activity and soluble protein content of sorghum leaves, while reducing leaf malondialdehyde content. Moreover, the GKI treatments increased leaf net photosynthetic rate. Under field conditions, yields of Jiliang 1 and Jiliang 2 were enhanced by an average of 17.1% and 19.1%, respectively. In conclusion, GKI seed dressing treatment effectively promoted the growth and development of sorghum under salt stress. It enhanced the antioxidant and osmoregulatory capacities of leaves, reduced the level of membrane lipid peroxidation, and improved net photosynthetic rate of leaves, which together improved the salt tolerance and sorghum yield.


Assuntos
Tolerância ao Sal , Sorghum , Giberelinas/metabolismo , Giberelinas/farmacologia , Cinetina/farmacologia , Cinetina/metabolismo , Antioxidantes/metabolismo , Ácido Butírico/metabolismo , Ácido Butírico/farmacologia , Grão Comestível
12.
Biomed Environ Sci ; 36(8): 732-742, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37711085

RESUMO

Objective: To investigate the distribution and antimicrobial susceptibility of causative microorganisms recovered from patients with intra-abdominal infections (IAIs). Methods: A total of 2,926 bacterial and fungal strains were identified in samples collected from 1,679 patients with IAIs at the Peking Union Medical College Hospital between 2011 and 2021. Pathogenic bacteria and fungi were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing (AST) was performed using the VITEK 2 compact system and the Kirby-Bauer method. AST results were interpreted based on the M100-Ed31 clinical breakpoints of the Clinical and Laboratory Standards Institute. Results: Of the 2,926 strains identified, 49.2%, 40.8%, and 9.5% were gram-negative bacteria, gram-positive bacteria, and fungi, respectively. Escherichia coli was the most prevalent pathogen in intensive care unit (ICU) and non-ICU patients; however, a significant decrease was observed in the isolation of E. coli between 2011 and 2021. Specifically, significant decreases were observed between 2011 and 2021 in the levels of extended-spectrum ß-lactamase (ESBL)-producing E. coli (from 76.9% to 14.3%) and Klebsiella pneumoniae (from 45.8% to 4.8%). Polymicrobial infections, particularly those involving co-infection with gram-positive and gram-negative bacteria, were commonly observed in IAI patients. Moreover, Candida albicans was more commonly isolated from hospital-associated IAI samples, while Staphylococcus epidermidis had a higher ratio in community-associated IAIs. Additionally, AST results revealed that most antimicrobial agents performed better in non-ESBL-producers than in ESBL-producers, while the overall resistance rates (56.9%-76.8%) of Acinetobacter baumanmii were higher against all antimicrobial agents than those of other common gram-negative bacteria. Indeed, Enterococcus faecium, Enterococcus faecalis, S. epidermidis, and S. aureus were consistently found to be susceptible to vancomycin, teicoplanin, and linezolid. Similarly, C. albicans exhibited high susceptibility to all the tested antifungal drugs. Conclusion: The distribution and antimicrobial susceptibility of the causative microorganisms from patients with IAIs were altered between 2011 and 2021. This finding is valuable for the implementation of evidence-based antimicrobial therapy and provides guidance for the control of hospital infections.


Assuntos
Coinfecção , Infecções Intra-Abdominais , Humanos , Antibacterianos , Escherichia coli , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Estudos Retrospectivos , Staphylococcus aureus , Infecções Intra-Abdominais/tratamento farmacológico , Infecções Intra-Abdominais/epidemiologia , Candida albicans
13.
J Org Chem ; 88(14): 9927-9940, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37432753

RESUMO

An array of redox-neutral alkylation/cyclization cascade reactions of N-functionalized acrylamides with cycloalkyl hydroperoxides were achieved via the alkoxyl radical-triggered C-C bond cleavage. Through adjusting the radical acceptors on the N atom, a variety of keto-alkylated chain-containing azaheterocycles, including indolo[2,1-a]isoquinolin-6(5H)-ones, quinoline-2,4-diones, and pyrido[4,3,2-gh]phenanthridines were constructed by a one-pot procedure with good yields and excellent functional group tolerance.

14.
Org Biomol Chem ; 21(28): 5855-5860, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37401815

RESUMO

An efficient iron-catalyzed alkoxyl radical-mediated C-C bond cleavage/phosphorothiolation cascade is presented. This protocol features mild and redox neutral conditions, wide substrate scope and easy scalability, allowing straightforward access to functionalized S-alkyl organophosphorus compounds in moderate to good yields.

15.
Org Lett ; 25(30): 5563-5568, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37477589

RESUMO

A redox-neutral copper-catalyzed cascade reaction involving alkoxyl radical-mediated ring expansion/1,4-difunctionalization of 1,3-enynes was developed, offering a straightforward approach to the tetra-substituted allenes with macrolactone, CN, and CF3 functional groups. Remarkably, incorporation of the NH2 group onto the 1,3-enyne moiety enabled further cyclization to give a unique scaffold containing a lactone and an indole moiety.

16.
Org Lett ; 25(23): 4329-4334, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37262417

RESUMO

An inexpensive iron-catalyzed alkoxyl radical-induced C-C bond cleavage/gem-difluoroalkylation cascade is presented. Regulated by the structure of alkoxyl radical precursors, fluorinated distal diketones were synthesized through a ring-opening strategy and difluoroalkylated medium-sized lactones and macrolactones were constructed via a ring-expansion strategy. Both protocols proceeded under mild and redox neutral conditions with a broad substrate scope and good functional group compatibility.


Assuntos
Ferro , Cetonas , Lactonas , Catálise
17.
Chem Sci ; 14(19): 5220-5225, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37206389

RESUMO

An efficient alkoxyl radical-triggered ring expansion/cross-coupling cascade was developed under cheap metal catalysis. Through the metal-catalyzed radical relay strategy, a wide range of medium-sized lactones (9-11 membered) and macrolactones (12, 13, 15, 18, and 19-membered) were constructed in moderate to good yields, along with diverse functional groups including CN, N3, SCN, and X groups installed concurrently. Density functional theory (DFT) calculations revealed that reductive elimination of the cycloalkyl-Cu(iii) species is a more favorable reaction pathway for the cross-coupling step. Based on the results of experiments and DFT, a Cu(i)/Cu(ii)/Cu(iii) catalytic cycle is proposed for this tandem reaction.

18.
Asian J Androl ; 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37026191

RESUMO

Phosphodiesterase (PDE) inhibitors can improve sperm motility in patients with asthenozoospermia. However, the most commonly reported nonselective PDE inhibitor pentoxifylline and PDE5 inhibitor sildenafil have the disadvantages of requiring a high concentration and destroying sperm integrity. We examined the PDE10A inhibitor PF-2545920 to compare its ability to promote sperm motility with that of pentoxifylline and sildenafil. After seminal plasma was discarded, several semen samples were subjected to four treatments (control, PF-2545920, pentoxifylline, and sildenafil) to evaluate their ability to affect motility, viability, and spontaneous acrosome reactions. Intracellular calcium and adenosine triphosphate (ATP), mitochondrial membrane potential, and penetration through viscous medium were assessed by flow cytometry, luciferase, and hyaluronic acid after treatment with PF-2545920. Statistical analyses were performed using the analysis of variance statistical test. PF-2545920 elevated the percentage of motile spermatozoa compared to the control, pentoxifylline, and sildenafil groups at 10 µmol l -1 ( P < 0.01). It is less toxic to GC-2spd mouse spermatocytes cells and spermatozoa and causes fewer spontaneous acrosomal reactions ( P < 0.05). PF-2545920 also increased mitochondrial membrane potential ( P < 0.001) and altered intracellular calcium ( P < 0.05) in a dose-dependent manner, including increasing sperm hyaluronic acid penetrating ability ( P < 0.05). Therefore, PF-2545920 might be an excellent choice for stimulating the sperm motility.

19.
Chem Commun (Camb) ; 59(28): 4189-4192, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36939750

RESUMO

Dimensionality plays a vital role at the nanoscale in tuning the electronical and photophysical properties and surface features of perovskite nanocrystals. Here, 3D and 1D all-inorganic CsPbBr3 nanocrystals were chosen as model materials to systemically reveal the dimensionality-dependent effect in photocatalytic H2 evolution. In terms of facilitating photoinduced electron-hole pair separation and charge transfer, as well as inducing proton reduction potential with the presence of fewer Br vacancies, 1D CsPbBr3 nanorods gave about a 5-fold improvement for solar H2 evolution.

20.
Org Lett ; 25(8): 1336-1341, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36815835

RESUMO

A concise Fe-catalyzed alkylazidation of α-trifluoromethylalkenes via a C-C bond cleavage/radical addition/azidation cascade is described. This protocol features a broad substrate scope, excellent functional group compatibility, and the ability to be performed on a gram scale, thus offering a practical and step-economic approach to the synthetically useful tertiary α-trifluoromethyl azides.

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